1979 camaro engine smoking

briangearhead

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Make
Chevy
Model
Camaro
Year
79
Miles
1000
Engine
355 sbc
I have a 79 camaro with a 355 sbc voodoo roller cam .. I put this engine in my car ruffly a 1000 miles on it .. this engine was sound and in excellent condition .. never ever smoked .. I add the Holley sniper EFI to the car for better fuel economy ... ran in to problems with it over fueling the engine .. called tech support finally figured out that the efi needed to be re calibrated... before figuring this out I kept having to change the oil because of the fuel thinning the oil thinking that's what was causing it to smoke Blue when the engine is reved ... this car had not seen the road yet since it has been a 7yr project.. car runs excellent but smokes blue if reved ... I'm worried it could be rings .. or valve guide seals ? ... any tips on narrowing this down with out tearing the engine completely down ?
 

grcauto

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Valve stem seals will smoke on startup but not like you describe that would be rings.
 

billr

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What do you have for a PCV system? That is another place a lot of oil can get sucked into the intake and burned.
 

briangearhead

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Valve stem seals will smoke on startup but not like you describe that would be rings.
Yeah I'm worried it is the rings it will sit and idle all day and not smoke at all but you give her the sauce and out comes the blue smoke ... the EFI was pour gas in so fast that it would actually hydro lock the engine and that's when I the holley tech had me run all these test and found out that I had to go in to the computer and do a re calibration... but I think it was to late at that point the damage was already done
 

billr

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Did you have the same breathers, and no smoke, before the EFI was added? Are you sure the smoke is coming out the tailpipe, not just a vague cloud behind the car?

I presume the smoke is bluish, not black or white, correct?

Have you done compression and leak-down tests? I would do both, they can give slightly different clues and you want to have all the info you can get.

What rpm do you have to get to before the smoke starts? Does it matter how much load (MAP) the engine is at?

Can you post/link a video showing the smoke?

Frankly, I think you are going to have to pull the engine apart for inspection. but I have hydro-locked engines with fuel, and they had no apparent damage. Oh, consider getting a boroscope/camera to take a peek in the cylinders, those are getting pretty cheap with todays camera tech.
 

briangearhead

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Did you have the same breathers, and no smoke, before the EFI was added? Are you sure the smoke is coming out the tailpipe, not just a vague cloud behind the car?

I presume the smoke is bluish, not black or white, correct?

Have you done compression and leak-down tests? I would do both, they can give slightly different clues and you want to have all the info you can get.

What rpm do you have to get to before the smoke starts? Does it matter how much load (MAP) the engine is at?

Can you post/link a video showing the smoke?

Frankly, I think you are going to have to pull the engine apart for inspection. but I have hydro-locked engines with fuel, and they had no apparent damage. Oh, consider getting a boroscope/camera to take a peek in the cylinders, those are getting pretty cheap with todays camera tech.
Basically before I put the engine in the car I went through and put all new gaskets in the engine just for peace of mind ,put the engine in the car started it on the carb that I ran on it before .. as per the directions of the holley EFI system .. recommend having a running engine before installing the EFI system "less problems
I ran through car several times checking for leaks as you usually have a few on new gaskets /complete engine install ... it never smoked ran perfectly ... installed the EFI ... and problems started happening ... over fueling , hydro locking the engine .. with a high torque mini starter at that .. turning the engine oil to water ... NOT LITERALLY.. just as thin and runny ... I even did a test on the oil ... after draining it ... lighting a little bit on fire to see how combustible it was .. oh yeah it had alot of gas in it .. anyway got the efi straightened out .. all was good .. but was smoking ... .. it will smoke even with the valve covers completely off .. .. it has a brand new pypes full exhaust system duals ran out the back .. yes the smoke clearly comes out the exhaust.... and just a few taps of the gas can make it smoke .. 2000 -3000 rpm ... I do have a bore scope ...
 

grcauto

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Is your compression up where it was when carbureted? I know you washed out the cylinders but they should be back in good order after running for a full heat cycle or two. I'm thinking that it may have been running with the cylinders washed out and it scrubbed the rings.
 

billr

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Is the exhaust system fully split, can you tell if smoke is equally from both banks?

I'll eagerly wait to hear what you see with the scope.
 

briangearhead

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Is the exhaust system fully split, can you tell if smoke is equally from both banks?

I'll eagerly wait to hear what you see with the scope.
Exhaust has the "x" pipe for balance .. yes would be alot easier if they were separate pipes atleast I'd be able to narrow it down to witch bank ... but not the case ...probably will be the weekend before I can get time to use the scope ... will up date after that
 

billr

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You could pull the plug leads on one bank at a time. It will run (rough) and be drivable (poor power) that way, but don't do it much if you have cats. Cats don't like a lot of unburned fuel if they are hot. If the cats are before the "X" pipe, then even that probably won't be a problem.
 

briangearhead

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You could pull the plug leads on one bank at a time. It will run (rough) and be drivable (poor power) that way, but don't do it much if you have cats. Cats don't like a lot of unburned fuel if they are hot. If the cats are before the "X" pipe, then even that probably won't be a problem.
Well this is all old school .. no cats , all it has is o2 senor for the EFI down by the header collector ... I'll see if I can upload a video of it running
 

billr

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Yeah, even as I was wring that cat stuff I figured it was probably moot...
 

briangearhead

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Yeah, even as I was wring that cat stuff I figured it was probably moot...
Well sorry I've tried all morning to upload a video and it keeps saying file does not have allowed extension... not sure if it this site or what ? I can send videos all day through my messenger... but for some reason it's not letting me ..
 

billr

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Send PM here to "jordanr", he is our admin and can probably help you post it.

Have you tried running with plugs disabled on one bank?
 
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